Need a source for a fuel pressure gauge inline adapter.

[wtd]

I'm trying to test the fuel pressure and check for fuel pressure bleed down on this 99 Cavalier that we just bought. I have a Mac 1100MS master fuel pressure kit. The car has 3/8" fuel line and the adapter in the kit for 3/8 only has it on the metal side of the adapter. The plastic quick connect end is smaller and won't fit on the barb on the fuel rail where the line from the tank attaches. Nothing else in the kit will work.

This is what the adapter looks like that is in my kit. I cannot find any information anywhere that tells me if any of these type adapters are 3/8 on both ends.
https://www.amazon.com/OTC-OTC51852...0dd17af62e58e048653f961&qid=1754338967&sr=8-1

 

[GSCJR]

It's been a while, does it not have the typical GM MPFI schrader valve for testing pressure?

 

[Trav]

Is it the 2.2 or 2.4?

 

[wtd]

It's been a while, does it not have the typical GM MPFI schrader valve for testing pressure?

No.

 

[wtd]

Is it the 2.2 or 2.4?

2.2L

 

[Timmastertech]

I built my own. My fuel pressure test kit has an inline adapter with hose barbs on each end and a 1/4 inch flare (standard GM fuel pressure test fitting) in the middle. I use fuel injection hose (not fuel line hose, injection hose is rated to higher pressure) and nylon fuel line repair fittings from the parts store to adapt to the factory unions.

 

[GSCJR]

I built my own. My fuel pressure test kit has an inline adapter with hose barbs on each end and a 1/4 inch flare (standard GM fuel pressure test fitting) in the middle. I use fuel injection hose (not fuel line hose, injection hose is rated to higher pressure) and nylon fuel line repair fittings from the parts store to adapt to the factory unions.

This might be the only solution @wtd. I went and looked at an old manual from my NAPA FI system cleaner and it only has 5/16" and 3/8" hairpin connectors; it truly is odd that yours doesn't fit.

 

[wtd]

I built my own. My fuel pressure test kit has an inline adapter with hose barbs on each end and a 1/4 inch flare (standard GM fuel pressure test fitting) in the middle. I use fuel injection hose (not fuel line hose, injection hose is rated to higher pressure) and nylon fuel line repair fittings from the parts store to adapt to the factory unions.

I may have to do that. My kit also has that inline adapter that you are talking about. I will see if my parts store has the fuel line repair fittings. Thanks.

 

[wtd]

This might be the only solution @wtd. I went and looked at an old manual from my NAPA FI system cleaner and it only has 5/16" and 3/8" hairpin connectors; it truly is odd that yours doesn't fit.

My kit has both the 5/16 and 3/8 hairpin connectors but the one side of the 3/8 is not 3/8 but looks to be the smaller 5/16.

I called Mac today and talked to someone in their tech support and they could not give me an answer as to whether or not the black female part of the 3/8 connector is also supposed to be 3/8 or not. I told him that it doesn't make sense why their 3/8 adapter would not have the same size on each side of it. He is going to contact their product development team and see what they say.

This is pretty frustrating to say the least.